QF821 Sun 12/8 - Weird engine vibration VH-TJJ
 

Okay so I was on QF821 Sun 12/8 from memory VH-TJJ

Just before we started the decent (5 mins prior) there was a vibration coming from the left engine...

It was not the speed brakes (may be the wrong term)

Best way to describe the sound was like a helicopter engine and also the noise from your car if you open two rear windows at high speed..

A vibration/thudding noise...

Continue until just before landing... Reverse thrust was used on both engines upon landing...

As soon as the engines were switched off, there were two engineers with torches looking at the engine...

Any thoughts ? Was the first time in hundreds of flights where I was slightly worried about my safety....